Apparatus for processing plastic material



Dec. 12, 1950 H. HARRIS ETI'AL ,7

APPARATUS FOR PROCESSING PLASTIC MATERIAL Filed June 11, 1946 '7Sheets-Sheet 1 Fig. J

Dec. 12, 1950 HHARHS ETAL 2,533,796

APPARATUS FOR PROCESSING PLASTIC MATERIAL Filed June 11, 1946 "7Sheets-Sheet 2 Mama Dec. 12 1950 H. HARRIS ETAL 2,533,796

APPARATUS FOR PROCESSING PLASTIC MATERIAL Filed June 11, 1946 7Sheets-Sheet 3 Fly. 3

Deg. 12, 1950 H. HARRIS ETAL 2,533,796

APPARATUS FOR PROCESSING PLASTIC MATERIAL Filed June 11. 1946 7Sheets-Sheet 4 92 100. g lOZ g 64 1 L II I W J E D A Ha befl'flafjz's 5:4 Lezzz fM e,

HI. HARRflfi ETAL 7 2533 796 APPARATUS FOR PROCESSING PLASTIC MATERIALFiled June; 11, 1946 '7 Sheets-Sheet 5 L A m m R R A H H APPARATUS FORPROCESSING PLASTIC MATERIAL 7 Sheets-Sheet 6 .Filed Jung 11, 1946 w w rw Mi wam ELM Dec. 12, 1950 H. HARRIS ETAL APPARATUS FOR PROCESSINGPLASTIC MATERIAL Filed June 11, 1946 7 Sheets-Sheet 'T i W n 1.87

, J31 2:: @1 185 19.2 "I; L j) l I @I Q l K' .176 76 -l86 76 175 171.190 W .182 I l I I i/o3 II 180 l .5 z .270 l l7 615 18 L g7 .l 7 l I lH11 1921? Mb,

cuzd Lar'mZfM Wafe,

than, Elm/W 4.

Patented Dec. 12, 1950 APPARATUS FOR PROCESSING PLASTIC MATERIAL HubertHarris and Lamar Mime Ware, Auburn, Ala., assignors to Auburn ResearchFoundation, Auburn, Ala, a corporation of Alabama Application June 11,1946, Serial No. 676,040

11 Claims.

The present invention relates to an apparatus for extruding plasticmaterial, and particularly for extruding food materials of relativelyfine texture such as sweet potatoes. The invention is particularlyconcerned with such materials having substantially no undesirableforeign matter therein such as fibers or pulp, or materials from whichsuch matter has been removed.

The apparatus of the present invention departs radically from prior artdevices of similar purpose, in that the plastic material is fed inwardlyto the center of rotation of a rapidly turning impeller, the materialbeing discharged from the periphery of the blades of the impeller bycentrifugal force. The material thus discharged is simultaneously forcedinto a plurality of passages extending from the periphery of theimpeller, said passages having distribution control means therein toregulate the flow and quantity of the material passing therethrough.Each of the aforesaid passages in turn connects with a number of smallerdischarge conduits which are likewise provided with similar distributioncontrol means. Each of said conduits terminates in an individualextrusion die through which the material is continuously orintermittently discharged at the desired rate of flow and in the desiredform and condition.

A principal object of the invention is to provide apparatus of the abovecharacter wherein the discharge of the material through the extrusiondies may be controlled with great refine ment. Specifically, theinvention involves control of the distribution of the material throughthe primary passages mentioned above, as well as through the smallerconduits, a number of the latter leading from a single passage. Inassociation with the previously referred to control devices, theinvention includes means for regulating the speed of the impeller, aswell as a novel form of conveyor which feeds the material to theimpeller.

An important object of the invention is to provide such apparatus havinga novel form of screw conveyor which receives the plastic materialaxially from its end and inwardly from the periphery of its rotatingblades, and discharges the material into the center of the impeller.

Another object of the invention is to provide an impeller and animpeller chamber which are relatively narrow in the direction of theaxis of the impeller as compared with the diameter of the chamber,whereby the material acted upon by the impeller is substantiallyconfined against axial movement with respect to the impeller and isdischarged from its periphery with substantial centrifugal force. Infact, the axial dimension of the chamber is substantially less than theradius of said chamber or the lengths of the impeller blades.

Another object of the invention is to provide extruding apparatus of thetype referred to wherein the material discharged from the impeller issub-divided into separate controlled channels of flow further leading toseparate controlled extruding dies.

Another object of the invention is to provide extruding apparatusincluding die heads which may be conveniently removed for the attachmentof substitute die heads with extruding openings of difierent form, sizeor character.

It is also an object of the invention to provide apparatus of thecharacter referred to having a novel form of container scraping meansassociated therewith, and particularly such means which is adjustablefor use with containers of various sizes and shapes.

Various other objects and advantages of the invention will becomeapparent as the description progresses, including the facility withwhich the machine may be disassembled and assembled for substitution orreplacement of parts, or for removal of certain of the elements of themachine in order to clean the same. Throughout the specification, theimportant feature of the apparatus wherein a controlled product isobtained will be apparent.

In the drawings, which are not intended to restrict the invention exceptas defined in the appended claims Figure l is a side elevational view ofthe apparatus,

Figure 2 is an end view of the apparatus viewed from the left of Figure1,

Figure 3 is a top plan view of the apparatus,

Figure 4 is an enlarged vertical sectional view taken along the line i iof Figure 3, showing particularly the impeller chamber and the impeller,

Figure 5 is a partial front elevational view of the extrusion assemblywhich depends from the impeller chamber, the front wall of the assemblybeing partially broken away to show the interior thereof,

Figure 6 is a transverse vertical sectional view through the removabledepending extrusion assembly, taken, for instance, along the line B6 ofFigure 5,

similar to Figure 6, showing particularly the distribution control meansin an almost closed position,

Figure 8 is a partial horizontal sectional view the top scraper bladestaken on the line 2 52 of Figure 10, and

Figures 13 through 1 7 show various shapes of extruding orifices whichmay be provided.

Referring to Figure l, the'material is fed. into i a downwardly andinwardly converging hopper H with the assistance of a chute C, ifnecessary, and if the material is delivered in cans or corn tainers, ascraping device R is employed operable above the chute and hopper.

' The material is. discharged from the lower end of the hopper H by afeed'screw F into the iinpeller chamber 1, where. a high speed impellerthrows the material into a plurality of passages and: .conduits later tobe described, which lead to a multiple. .di'e head. D. The material isdischarged in a controlled manner through plurailty of orifices ofselected size and character which are a part. ofthe die head, into traysor other suitable receptacles. which may be continuously moved. beneaththe die head D. The invention comprehends. refined control of thematerial throughout the process described from the time the material isinitially acted on by the feed screw F until it is discharged from. theorifices of. the extruding. die assembly D. These controls include: (1)control of the speed of the feed screw Band of the impeller in thechamber I, and control of the delivery from the former to the latter,(.2) two stages. of divided. and, sub- 1 4 variable speed base member is(such as the standard Reeves variable speed base), which may be mountedfor slidable movement in suitable guides carried by horizontal membersIt. The motor shaft drives a variable speed pulley 2B of any well knowntype such as the standard Reeves variable speed pulley), which isconnected by means of a belt 22 with a driven pulley 2% (Fig. 1). Thepulley 12 i, is keyed to the shaft S, the latter being supported insuitable bearings carried. by the frame members previously mentioned.The pulley 25 may be of a well-known type having conically shaped plateswhich are held in position by the tension of a spring, the beltoperating on different diameters between the, two plates in accordancewith the adjustment of the base it. The speed of the driven pulley 2-4and hence the speed of the impeller and feed screw shaft S may thus beVaried to control the condition and rate of delivery of the. plasticproduct as will be hereinafter apparent. The speed adjustment is thusaccomplished by inward and outward movements of the supporting base it,and this adjustment may be made by the turning of a lower hand, wheelto, which in tu n ro ates a s aft hav ng a threaded connection, with thebase it, it being understood that the shaft is held in any. suitablemanner against longitudinal movement so each. extruding orifice. as, to.size and shape of the mass of material being extruded, as well as of thelengths of perfectly formed material which is discharged fromthepriflcesl The impeller'ito be later described) is driven by a primarysource of power such as the elec- 'tric motor M. which indirectly drivesa shaftv S on'whi'ch the feed screw '1? and the impeller are mounted,the drive being through any convenient belt or mechanical "gearing withconvenient arrangements for changing speed of rotaticn of the shaftsl'within any limits desired.

The'apparatus maybe mounted on base or frame members ill, corner legs 12and i l. may be ,rovided at opposite ends of the machine constitutingsupports on which most of. the principal elements of the machine aremounted, as will be apparent from the drawings without detaileddescription.

Referring to Figure 2, the motor M and its shaft [5 may be'mounted foradjustment from that its turning will translate, the, base 16. Thisjustmen l o e a comp she a similar hand wheel, 3t positioned at aconvenient point in the upper part of. the machine which turns a shaft65 extending across the frame of the machine, therebeing intermeshingbeveled gears 53 as shown in, FgigureB which turn a. sub.- stantiallyvertical shaft ill; suitably journaled on the frame, the latter likewiseserving to turn the shaft 32 through lower connecting similar beveledgears d2 as best shown in Figure 1.

It will be understcqd that the mechanism for controlling, or changingthe speed of the, shaft as ju t scribed m y ake ther. forms. su h asconventional. change speed gears, the means indicated in the drawingsbeing illustrative only.

Referring, to Fi ure, 4-, the inner wall of the hopper comprises anupper flat vertical surface is, which inclines outwardly at El! and thenextends, vertically downwardly as at 52. to form the front. faceof' theimpeller chamber I. 1mmediately above thehlower rounded bottom surface54 of the hopper, and. centrally thereof; the upper vertical wall 52 isprovided with an inlet openingbli of. slightly larger diameter than thatof the largest flight of the feed screw, this opening being covered by,an outwardly extending flange hood '58 which is substantiallysemi-circular in end'section. The hood 5?) is open at its outer end asshown.

The side or bottom edges of the hood 58 extend downwardly around andover the inner part of the flights F approximately to the center line ofthe shafts. The hood may be adjusted vertically by means of a slottedintegral plate 59 havinga handle 59", the plate being retained by a wingnut 6i threaded into the'wall 52; Obviously, movement of thehood'iififrom and toward the feed screw will respectively increaseorreduce the rate-of-flow of material to the impeller chamber- Thehopper I-lalso includes a lower vertical plate 66 which defines thelower front face of the impeller chamber 1, as well as the frontfaces ofthe plurality of outlet passages for theplas tic leading tothe extrusiondies.

The inner face of the impeller chamber is formed by a vertical plate 62which is substantially circular in its upper portion, which plate widenslaterally at its lower portion 63 where it is bent inwardly as at E4 andthence downwardly as at 66 to form a rear wall enclosing support for thedischarge passages and conduits leading to the extrusion die assembly D.As shown in Figure 4, the plate 52 is rigidly attached to the frame andprovided with a substantially centrally located opening 68 for the shaftS. The hopper plate 52 may be locked to the inner face of the plate 62by suitable accessible and detachable locking means as indicated at 6 inFigure 4.

As will be apparent from Figures 2 and 3, the entire front face of theapparatus comprising the hopper H and depending front vertical plate maybe hinged for swinging movement to open up the impeller and distributionchambers, appropriate hinges suitably connected with the frame beingshown at 65, there being cooperating locking means 66 spaced around theengaging edges of the fixed and hinged plates.

The plate t2 has integral therewith an edge flange or wall 10 ofsubstantially circular form which extends around and closes the upperpart of the impeller chamber, there being a continuation of this wall(not shown) but which extends laterally outwardly and downwardly to formthe sides of the passages leading from the impeller chamber to theextrusion dies as hereinafter described.

As indicated in Figures 2 and 4, there are a plurality of suitablycurved impeller blades l2 keyed to the shaft S within the chamber 1,said plates presenting radially convex surfaces toward the direction oftheir clockwise movement as viewed in Figure 2. It will be noted thatthe width of the impeller chamber and the width of the impeller blades(Figure l) is substantially less than the radius of the impellerchamber, or the radial lengths of the impeller blades. By reason of thisconstruction, and because the plastic material is fed centrally into theimpeller chamber and toward the impeller blades, the material will berapidly and positively forced radially outwardly and released at thelower side of the impeller chamber into the distributing channels andconduits later to be described. There is thus no axial movement of thematerial from the impeller chamber, the limited axial movement beingconfined to that of delivery of the material into the impeller chamber.

The feed screw F comprises helical flights which gradually increase indiameter from an outer central point 14 to an inner terminal flight 75which is of diameter almost as great as the inlet opening 56. The finalflight 16 of the feed screw terminates short of the plane of rotation ofthe outer edges of the impeller 12 and within the passage defined b theside cover or hood 58. The screw is generally conical in form, the sideof the cone being of substantially the same shape as the lower innerwall of the front 54 of the hopper. It will thus be apparent thatmaterial in the hopper l-I will flow or be drawn into the spaces betweenthe flights of the feed nut both axially from its pointed end 14,downwardly from above the screw, and inwardly from the sides of thescrew (Figure 3). This manner of feeding the material, with the base ofthe cone of the screw presented to the impeller, gives a progressivefeed from the hopper with no tendency for the material to be thrown fromthe screw by centrifugal force. Due to the shape of the feed screw, andthe shape of the hopper, the former is at the very bottom of the hopperand its flights are in substantial contact with the bottom of the hopperas shown in Figure 4. There is thus no possibility that material willaccumulate in the hopper without being fed to the impeller, there beingno space beneath the feed screw where this could take place.

As shown in Figure 2, the distribution and extrusion assembly dependsbelow the impeller chamber, and this assembly may be wider than thediameter of the impeller chamber as is apparent in this figure. Thefront and rear walls 64] and 63 of the distribution and extrusionchamber define a plurality of distribution passages leading from thelower periphery of the impeller chamber, there being passages extendingthroughout almost the lower of said chamber. There are approximatelyeight of such passages between point 89 and points 82. Each of thesepassages, designated as 84 in Figures 2 and 5, is separated fromadjacent passages by vertical metal walls 86 carried by the front walltil. There are also lower vertical partition plates 88 carried by alower extension of the rear wall 63, which divide each passage into aplurality of conduits as shown in Figure 5. The lower wall of theimpeller chamber is formed by a plurality of curved plates 9t carried bythe front wall (it which are spaced vertically from the peripheral edgeof the impeller plates 12. Looking downwardly on these plates as inFigure 8, they are shown provided with diagonal openings 92 which extendfrom adjacent the inner wall 63 at the right-hand side of each passageas viewed from the front diagonally to adjacent the front wall 60 of thepassage at the left-hand side. It will be understood that, as viewed inFigures 5 and 8, the impeller blades in their rotation move from theright toward the left, and the diagonal arrangement of the ports oropenings 92 insure an even distribution of the plastic materialthroughout each of the passages 84.

Referring to Figure 6, the material passing through the slot 92 fallsonto the inner surface of the inclined wall 54 and is pressed down thesame by centrifugal force to enter the restricted throat portion 94 ofthe passage, although the material passing through the extreme left-handends of the slots e2 may fall directly into the throat 54. In order toregulate the quantity of material entering a particular passage 96!, orto cut off the'flow of material altogether into such passage, anadjustable closure plate lfiii (Figures 6 and '7) is mounted for slidingmovement beneath the plate 95, and this closure plate has an edge asshown by the dotted lines in Figure 8 of the same diagonal shape as theedges of the opening 92. The closure plate illli is carried by aforwardly extending rod Hi2 which passes through an opening in the frontwall iiii, and its outer end is threaded into a nut we having a head fitwhich retains the nut against axial movement. By turning the nut, therod I22 is moved inwardly and outwardly to adjust the closure plate i 36throughout the slot or opening as. The above constitutes distributioncontrol for a relatively greater mass of the material fed by centrifugalforce from the impeller chamber into the passage 3 5 and thence into therestricted throat 94 of said passage. The passage 85, and the throat 94permit masses of the material to build up therein under action of theimpeller, so that even flow from the extrusion orifices will result.

ateatoe Beierrins' t9.- Eisure 6.2, the rear: wall or; the; rel-T st,cted hroa qfiais formed. by upper pla e like or a, removable .die.shoe. ii 22, which curves in. weirdly atitslowerend as. at its- This;d-ie shoe. m y be removably attached to. the lower. end of therear plateby any suitable meanssuchz asbolts k4 5i having. wing nuts, 11-81.

The lower end of the. iront, plate, 5B: carries: an inwardly; directedflange i125]; which formssthe bottom of the throat portion, cc of the:passage 3Z4, thisfiangeleaving a. relatively small, passage i=2}?between. its. inner edge and: the forward faceof the rear plate it ofthe the shoe. In order to. adjust flow through each of the conduits I22thus, formed or to completely close oft any: one.

ofisaidi conduits, there is amovable closure plate l-Z li ml eachconduit, which isaoperated'v by a screw tilt: inithe same manner as:previously. described, to. closeofi the port e211: or: individuallyregulate the flow theret-hrough.

Referring: tov Figure 6, alaterally: extending plate 3381s suitablysecured in spaced relation to the wal-l' Hi: ('35 the die shoe H2 bybolts l3! and this platehas spaced threaded openings I32 therein wherebytheupper end of a suitably curved dieplate army be attached, the lowerends of said/platehaving a hook portion 53:? which engages ina suitablerecessi-B S in the lower outer face of the-die shoe. The die plate Hithas a plurality of extruding openings ororifices extending therethroughsame being designa ted as M in: Figures 5 and 6; 'Ifhe-parti-tion plates88 which define the side of thefinal narrow conduits leading to theextrudingorifices are carried by andbetween the inner; face-oi? the-dieshoe andthe plate li's-fi fixed theretofnfbari extending across the faceofthe dieassembly (Figures 2 and" 5) holds the upper edge of-tliecurveddie plate 3 rigidly in placei Extending longitudinally through, theentire die headg assembly is asha f t Hi l, the ends; of said shaftextending beyondthe side walls thereof as shown in Figure 5 and also asindicated in Fig. 2. There is a cutter arm I 35. having a curved cut t gblade in each of the extruding chambers se- "d to the shaft i to, sothat as said shaft is es: lated the blade is moved downwardly to cut 11;a, length of the. material, being extruded through the orifice lt-il;This may be done manually by an operatinghandle E52" as indicated inFigure or appropriate automatic driving means one o heshaft. its may b'r o ided; r e by the primary source of power through any uitable iminme ha ism... t. will e. un er stooda. conveyor is generally used in a55c a i nwi h t s app ra us whiehw llcarry ra moving, for instance, fromvleft to, right beneath the extrusion orifices Hic asin Figure 6. It ispos ible o so m h operation. f th uttin knives its so that lengths ofthe. material are cut off to drop into each tray, theorifice beingclosed when the spacebetween theadjacent trays is passing beneath-thedie. Itwillbe particularly noted that the cutting blade M33 is withinthe die plate 6,34, so that, the material extruded is, not affected or.distorted inits shape, by, the action of the knife.

Referring to Figures. 13 through 1? various other forms, ofthe-extruding orifices are shown, and it, willv be understood thatindividual, die platesv i fidmay beselectively appliedftovary they formof theextrudedmaierial, or to vary. the size and amount 'oi,ajstrinsmaterial. being extruded.

Any or all: of the; extruding orifices may: be. used atthesame time, orcertain of them may-housed intermittently, and, strings. of the plasticmate.- ri'als may-be discharged from the machine ofuniform contour, ordifferent shapes may be simultaneously discharged at the. diiierentorifices by varying the form of the orifices in a given plate, orbyusing several plates. having different orifices to form the front ofthe assembly. 7

From the above, it will be obvious that I have provided very refinedcontrol of the product from the time it is initially acted upon by thefeed screw F until it is discharged at the die orifices; As previouslystated, the apparatus departs radically from prior art devices where,for instance, thepressure exerted by'a helical screw isereliedon todirectly force the material through the dies, or where boaters areemployed topress or mash material through a screen or the like. In thecase of our machine the impeller rapidly builds up a high pressure bycentrifugal force, and refined: control means areprovided'to control theextrusion of this material. It is obvious that the eontrol may beexercised While the machine is in operation and while observing thedelivered product.

The can scraper R may be driven from a motor i551 suitably mounted onthe frame bybelts I52 and it?! through suitable-change speed pulleyarrangements 4-66 or any equivalent devices. liheshaft for the scraperis indicated at 58 and it extends upwardly at an angle above the hopperH and the-feed chute C, beingsupported in suitableantifriction bearingsas indicated in Figure 4.

Referring to Figure 9, the upper end of the shaft its has adjustablybut-rigidly fixed thereto.

cessed as at 89 to fit between the flanges. N4 of the brackets tit andN2, the upper outer corners or edges of said brackets being rounded offas at 1.82 so that the links H5 and Edit may pivot upwardly around theconnecting pivot pins 515, while being prevented from pivotingdownwardly beyond horizontal position becauseofthesquare lower edgesof'the flanges ofsaid' brackets;

which engage ledges ltson said links. Each of he links life and iiaispivoted asat lotto-spaced;

flanges E35 of brackets i filwhich are connected with vertical hard woodscraper blades E81. In a. manner. similar to that previously described,

the lower inner edges of the flanges. of the brackets, itiiare roundedso that theblades 581 moveinwardly asthelinksi756 and Liapivot'upwardly. the upper inner edges of said; flanges being square to preventtheir movementbeyond the horizontal position as viewed in. Figure 9.

The scraper, blades idlimay be of: any desired formv having anyoutwardly extending tapered scrapin edge. idaias shown in Figure 10; Atthe. upper ends of the scraper blades l8? Ol Z QSitBIy. extend ingtop'hard'wood scraper bars; i353: and 892: are, provided. Thesebars donot connect with; one; anothenbut are in side by side relation, onebar,- being connected to the top of one, of the side scrapers and theother bar being rigidly connect-1 ed to-the top of the otherside'scraper as by bolts 1 Thescraper is normally held in the. conditionshown inFigurc Qbythelow tension of springs, 1,95 which extends betweenhooks i533; fixed to;

the sha an h o s 21.1.9 w i a -attached to the lower brackets I86 on therespective side scraper bars till. When a container of material is to becleaned, it is placed over the top of the device as shown in Figure 9with the open end of the can extending downwardly, the engagement of thebottom of the can with the top of the cross bars i913 and H92 and theapplication of pressure by hand causing the side scraper bars 58! tomove downwardly with respect to the shaft Hill, the top scraper barsl9!) and H32 yielding horizontally with respect to one another to permitthe downward movement of the side scrapers H81. The downward movement ispermitted by the pivoting action of the links H6 and H3, which may bemoved to a horizontal position if the diameter of the can requires it,although it will be apparent that the diameter of the container may be alimiting factor on the degree with which the device may be expanded to acondition short of maximum. If desired, a bolt with a head slightlywider than the shaft its (not shown), may be threaded into the upper endof said shaft, and may be adjusted inwardly and outwardl by a lock nutto provide a stop limiting the downward movement of the top scraperbars.

Bolts and nuts 93 are shown for securing the top scraper bars I95 andI92 to the upper ends of the blades. If refined adjustments of thescraper are required, the top bars may be so secured by single wing nutsin order that the bars may be adjusted at right angles to the shaft 568after the adjustment of brackets H8, H2 has been completed.

When a container is thus applied to the scraper, suitable electriccontrols are actuated to turn the shaft 3 38 at the desired speed, andthe side blades lfil will scrape the side of the can and the top bladeswe and 592 will scrape the inner end of the container, discharging thematerial into the chute C and the hopper H.

The scraping device automatically accommodates itself to cans of varioussizes of any given shape. The device may be adjusted for use withcontainers of shapes other than cylindrical, for

instance, containers of flared shape, by appropri- 5 ate adjustment ofthe respective center brackets iii} H2 along the shaft I68, same beingsecured by set screws ill. This adjustment may be made by moving one orboth of the brackets iii] and m, but a simple adjustment can be made bymerely moving the upper bracket ill 1" or example, downwardly a shortdistance on the shaft 558 and then rigidly securing the same in order toadapt the device for action on a flared container.

It will be apparent that we have provided apparatus and methods whichwill insure a high degree of control in the extrusion of plastics of thementioned herein. It will also be apparent that the machine is of simpleand conveni nt design, and capable of being quickly and easil takenapart for replacement of parts, or for purposes of cleaning.

We claim:

1. Apparatus for processing plastic materials comprising an impellerchamber, a feed hopper for the material adjacent one end of saidchamher, a drive shaft extending centrally into said chamber, impellerblades on said shaft, means for rotating said shaft and said blades athigh. speed in said chamber, said chamber having an inlet leading fromsaid hopper into the center of said chamber, and means in said inletsyn"- chrcnously driven with said impeller blades for continuouslyfeeding the material into said chamid her and between said bladesadjacent their center of rotation, said chamber being enclosed by a sidewall except for a discharge passage leading from its periphery at oneside thereof.

2. Apparatus as set forth in claim 1 wherein said means synchronouslydriven with said impeller blade comprises a screw conveyor driven by anextension of said drive shaft into said feed hopper.

3. Apparatus as set forth in claim 2 wherein said screw conveyor isformed of substantially helical flights which reduce in radius tosubstantially a point at one end of the conveyor, the larger end of saidconveyor extending substantially into the inlet opening of said chamber.

4. Apparatus as set forth in claim 1 wherein said feed hopper has aninner bottom side in clined downwardly toward said inlet in saidimpeller chamber and wherein said synchronously driven means comprises aconveyor formed of substantially helical flights substantially coneshaped in outside contour, said conveyor being positioned so that itspoint projects from said opening with said flights in substantialcontact with said inclined inner bottom side of the feed hopper.

5. Apparatus for processing plastic materials comprising an impellerchamber, a feed hopper for the material adjacent one end of saidchamber, a drive shaft extending centrally into said chamber, impellerblades on said shaft, means for rotating said shaft and said blades athigh speed in said chamber, said chamber having an inlet leading fromsaid hopper into the center of said chamber, means in said inletsynchronously driven with said impeller blades for continuously feedingthe material into said chamber and between said blades adjacent theircenter of rotation, said chamber being enclosed by a side wall exceptfor a discharge passage leading from its periphery at one side thereof,and an outlet at the outer termination of said passage, whereby thematerial is continuously fed into the center of said impeller anddischarged from said side of said chamber by the centrifugal forceasserted by high speed rotation of said impeller blades and extrudedfrom said outlet by pressure of the material built up in said dischargepassage by said impeller.

6. Apparatus as set forth in claim 5 wherein means are provided tochange the speed of rotation of said. impeller for varying the deliveryof extruded material through said outlet.

7. Apparatus as set forth in claim 5 wherein said passage and saidimpeller chamber are separated by a plate having an elongated openingtherethrough arranged diagonally with respect to the direction ofmovement of the periphery of the impeller blades past said plate.

8 Apparatus for processing plastic materials comprising an impellerchamber, a feed hopper for the material adjacent one end of saidchamher, a drive shaft extending centrally into said chamber, impellerblades on said shaft, means for rotating said shaft and said blades athigh speed in said chamber, the width of said chamber defined byopposite end walls being substantially less than its radius, saidchamber having an inlet through one end wall leading from said hopperinto the center of said chamber, the opposite end wall of said chamberbeing closed to prevent longitudinal movement of material through thechamber, and means in said inlet synchronously driven with said impellerblades for continuously feeding the material into said 1 1 chamber andbetween said blades adjacent their center of rotation, said impellerchamber bein enclosed by a side well except for a discharge passageleading from its periphery at one side thereof.

9. Apparatus as set forth in claim 8 wherein a plurality of separatedischarge passages are provided leading from the periphery at one sideof said impeller chamber, each of said separate passages having anopening at it outer end and an adjustable closure regulator to govern"the volume of material forced therethrough by said impeller.

10. Apparatus for processin plastic materials comprising an impellerchamber, a feed hopper for the material adjacent said chamber, a driveshaftextending centrally into said chamber, impeller blades on saidshaft, means for rotating said shaft and said blades at high speed insaid chamber, said chamber having opposite end Walls, one of said endWallshaving an inlet leading from said hopper into the center of saidchamber, said blades being of a width substantially equal to thedistance between said end Walls and being substantially' uninterruptedin contour from said shaft to their periphery, and means in said inletsynchronously driven with said impeller blades 11. Apparatus forprocessing plastic materials comprising an impeller chamber, a feedhopper chamber, and means in said inlet and driven by said shaft forcontinuously feeding material into said chamber.

I-IUBERT HARRIS. LAMAR MIMS WARE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Name Date 498,206 Denbeigh May 23, 1893 518,942.Duhrkop May 1, .1894 672,554 Henkel Apr. 23, 1991 1,010,175 Pooley Nov.28, 1911 1,158,908 Ehrhart Nov. 2, 915 1,709,405 Patitz Apr. 16, 19291,773,552 Sizer Aug. 19, 1930 1,777,294 Dellenbarger Oct. 7, 1930'1,887,138 Pefier Nov. 8, 1932 2,245,368 Thalman June 10, 1941 2,308,937

Schwab Jan. 19, 1943

